104 ECONOMIC ZOOLOGY 



wax. Many large apiaries are to be seen in California, often on a 

 sunny slope on the edge of a desert. In this state there is a succession of 

 flowers throughout the entire year whereas in colder climates there is 

 a winter season during which no honey is manufactured. The various 

 flowers visited by the honey bees, of which bees there are some 1500 

 species, often give a characteristic taste to the honey, as happens for 

 example, in some sections, when buckwheat is in bloom and the bees 

 swarm over the fields of white blossoms. It is said that honey is some- 

 times made poisonous by the bees visiting the flowers of Mountain 

 Laurel. 



Honey is not only a delicious food, but is a highly nutritive one; 

 it is also used in medicine. It is frequently adulterated with as much 

 as 75 per cent, glucose, which process, though it is a true adulteration, 

 does not injure the honey as food. 



Silk-worms. The manufacture of silk originated probably in China 

 about 3400 B. C. and is hence one of the oldest of human industries. 

 The raising of silk- worms was introduced into Europe in 552 A. D. and 

 into Virginia about 1600. The production of raw silk has never been 

 profitable in America because of the competition with cheap Italian 

 and Oriental labor for picking the cocoons and reeling the silk. 



The introduction of power looms, such as may be seen at Paterson, 

 N. J., a great silk centre, has revolutionized the manufacture of silk 

 goods, but in Canton, China, and doubtless in other places in the 

 Orient, the old-fashioned hand loom, crude and terribly slow, may still 

 be seen. 



China and Japan are great producers of raw silk and can probably 

 increase their supply almost indefinitely to keep up with the demand. 

 Japan exports some 11,000,000 pounds per year, 60 per cent, of which 

 comes to the United States. The original source of the raw silk is, 

 of course, the "silk-worm," the larvae of a moth, of which there are 

 15 to 20 species; the best known of these silk-worms is Bombyx mori, 

 whose habits are, briefly, as follows: 



The female lays from 200 to 500 eggs, which hatch, the following 

 spring, into tiny caterpillars; these larvae grow very rapidly, feeding 

 voraciously on mulberry leaves, until they are about 3 inches long, 

 molting several times; each larva then spins a cocoon of silk threads 

 from 2000 to 3000 feet long, taking about five days for the process. 

 The spinneretts are in the mouth and the silk-secreting glands (like 



